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From: Colton Lewis <coltonlewis@google.com>
To: kvm@vger.kernel.org
Cc: Alexandru Elisei <alexandru.elisei@arm.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	 Jonathan Corbet <corbet@lwn.net>,
	Russell King <linux@armlinux.org.uk>,
	 Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>, Marc Zyngier <maz@kernel.org>,
	 Oliver Upton <oliver.upton@linux.dev>,
	Mingwei Zhang <mizhang@google.com>,
	 Joey Gouly <joey.gouly@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	 Zenghui Yu <yuzenghui@huawei.com>,
	Mark Rutland <mark.rutland@arm.com>,
	 Shuah Khan <shuah@kernel.org>,
	Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>,
	 James Clark <james.clark@linaro.org>,
	linux-doc@vger.kernel.org,  linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,  kvmarm@lists.linux.dev,
	linux-perf-users@vger.kernel.org,
	 linux-kselftest@vger.kernel.org,
	Colton Lewis <coltonlewis@google.com>
Subject: [PATCH 01/21] arm64: cpufeature: Add cpucap for HPMN0
Date: Fri, 12 Jun 2026 19:28:49 +0000	[thread overview]
Message-ID: <20260612192909.1153907-2-coltonlewis@google.com> (raw)
In-Reply-To: <20260612192909.1153907-1-coltonlewis@google.com>

Add a capability for FEAT_HPMN0, whether MDCR_EL2.HPMN can specify 0
counters reserved for the guest.

This required changing HPMN0 to an UnsignedEnum in tools/sysreg
because otherwise not all the appropriate macros are generated to add
it to arm64_cpu_capabilities_arm64_features.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Colton Lewis <coltonlewis@google.com>
---
 arch/arm64/kernel/cpufeature.c | 10 +++++++++-
 arch/arm64/kvm/sys_regs.c      |  3 ++-
 arch/arm64/tools/cpucaps       |  1 +
 arch/arm64/tools/sysreg        |  6 +++---
 4 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 6d53bb15cf7bb..096545a6e4043 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -77,7 +77,7 @@
 #include <linux/percpu.h>
 #include <linux/sched/isolation.h>
 
-#include <asm/arm_pmuv3.h>
+#include <linux/perf/arm_pmuv3.h>
 #include <asm/cpu.h>
 #include <asm/cpufeature.h>
 #include <asm/cpu_ops.h>
@@ -560,6 +560,7 @@ static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
 };
 
 static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
+	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_HPMN0_SHIFT, 4, 0),
 	S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_DoubleLock_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_PMSVer_SHIFT, 4, 0),
 	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_CTX_CMPs_SHIFT, 4, 0),
@@ -2965,6 +2966,13 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
 		.matches = has_cpuid_feature,
 		ARM64_CPUID_FIELDS(ID_AA64MMFR0_EL1, FGT, FGT2)
 	},
+	{
+		.desc = "HPMN0",
+		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
+		.capability = ARM64_HAS_HPMN0,
+		.matches = has_cpuid_feature,
+		ARM64_CPUID_FIELDS(ID_AA64DFR0_EL1, HPMN0, IMP)
+	},
 #ifdef CONFIG_ARM64_SME
 	{
 		.desc = "Scalable Matrix Extension",
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index fa5c93c7a1352..c52873a6f91ed 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -3326,7 +3326,8 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 		    ID_AA64DFR0_EL1_DoubleLock_MASK |
 		    ID_AA64DFR0_EL1_WRPs_MASK |
 		    ID_AA64DFR0_EL1_PMUVer_MASK |
-		    ID_AA64DFR0_EL1_DebugVer_MASK),
+		    ID_AA64DFR0_EL1_DebugVer_MASK |
+		    ID_AA64DFR0_EL1_HPMN0_MASK),
 	ID_SANITISED(ID_AA64DFR1_EL1),
 	ID_UNALLOCATED(5,2),
 	ID_UNALLOCATED(5,3),
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps
index 811c2479e82d6..f8fb4a6395428 100644
--- a/arch/arm64/tools/cpucaps
+++ b/arch/arm64/tools/cpucaps
@@ -42,6 +42,7 @@ HAS_GIC_PRIO_MASKING
 HAS_GIC_PRIO_RELAXED_SYNC
 HAS_ICH_HCR_EL2_TDIR
 HAS_HCR_NV1
+HAS_HPMN0
 HAS_HCX
 HAS_LDAPR
 HAS_LPA2
diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg
index 6c3ff14e561e6..2d5cbc8ced114 100644
--- a/arch/arm64/tools/sysreg
+++ b/arch/arm64/tools/sysreg
@@ -1679,9 +1679,9 @@ EndEnum
 EndSysreg
 
 Sysreg	ID_AA64DFR0_EL1	3	0	0	5	0
-Enum	63:60	HPMN0
-	0b0000	UNPREDICTABLE
-	0b0001	DEF
+UnsignedEnum	63:60	HPMN0
+	0b0000	NI
+	0b0001	IMP
 EndEnum
 UnsignedEnum	59:56	ExtTrcBuff
 	0b0000	NI
-- 
2.54.0.1136.gdb2ca164c4-goog


  reply	other threads:[~2026-06-12 19:29 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-12 19:28 [PATCH v8 00/21] ARM64 PMU Partitioning Colton Lewis
2026-06-12 19:28 ` Colton Lewis [this message]
2026-06-12 19:28 ` [PATCH 02/21] KVM: arm64: Reorganize PMU includes Colton Lewis
2026-06-12 19:28 ` [PATCH 03/21] KVM: arm64: Reorganize PMU functions Colton Lewis
2026-06-12 19:28 ` [PATCH 04/21] perf: arm_pmuv3: Generalize counter bitmasks Colton Lewis
2026-06-12 19:28 ` [PATCH 05/21] perf: arm_pmuv3: Check cntr_mask before using pmccntr Colton Lewis
2026-06-12 19:28 ` [PATCH 06/21] perf: arm_pmuv3: Allocate counter indices from high to low Colton Lewis
2026-06-12 19:28 ` [PATCH 07/21] perf: arm_pmuv3: Add method to partition the PMU Colton Lewis
2026-06-12 19:28 ` [PATCH 08/21] KVM: arm64: Set up FGT for Partitioned PMU Colton Lewis
2026-06-12 19:28 ` [PATCH 09/21] KVM: arm64: Add Partitioned PMU register trap handlers Colton Lewis
2026-06-12 19:28 ` [PATCH 10/21] KVM: arm64: Set up MDCR_EL2 to handle a Partitioned PMU Colton Lewis
2026-06-12 19:28 ` [PATCH 11/21] KVM: arm64: Context swap Partitioned PMU guest registers Colton Lewis
2026-06-12 19:29 ` [PATCH 12/21] KVM: arm64: Enforce PMU event filter at vcpu_load() Colton Lewis
2026-06-12 19:29 ` [PATCH 13/21] perf: Add perf_pmu_resched_update() Colton Lewis
2026-06-12 19:29 ` [PATCH 14/21] KVM: arm64: Apply dynamic guest counter reservations Colton Lewis
2026-06-12 19:29 ` [PATCH 15/21] KVM: arm64: Implement lazy PMU context swaps Colton Lewis
2026-06-12 19:29 ` [PATCH 16/21] perf: arm_pmuv3: Handle IRQs for Partitioned PMU guest counters Colton Lewis
2026-06-12 19:29 ` [PATCH 17/21] KVM: arm64: Detect overflows for the Partitioned PMU Colton Lewis
2026-06-12 19:29 ` [PATCH 18/21] KVM: arm64: Add vCPU device attr to partition the PMU Colton Lewis
2026-06-12 19:29 ` [PATCH 19/21] KVM: selftests: Add find_bit to KVM library Colton Lewis
2026-06-12 19:29 ` [PATCH 20/21] KVM: arm64: selftests: Add test case for Partitioned PMU Colton Lewis
2026-06-12 19:29 ` [PATCH 21/21] KVM: arm64: selftests: Relax testing for exceptions when partitioned Colton Lewis

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